EPA Authorizes Navajo Nation to Carry Out Program that Protects Groundwater

The U.S. Environmental Protection Agency (EPA) is approving the Navajo Nation’s application to administer the underground injection control program for oil and gas-related injection wells.

The UIC program authorizes specific waste streams to be injected, and prescribes operating measures to ensure that underground sources of drinking water are protected. Under the Navajo Nation’s UIC program, the tribe will have authority to issue permits, conduct inspections, participate in enforcement actions and support the EPA’s annual reporting.

“Today, the Navajo Nation takes over an important program to protect the tribe’s groundwater resources—a vital source of drinking water,” said Wayne Nastri, administrator for the EPA’s Pacific Southwest region. “Together with their prior authorization to oversee public water systems, the Navajo Nation is now the first tribe in the nation to implement the two main regulatory programs under the federal Safe Drinking Water Act.”

The program will apply to roughly 400 existing oil and gas-related injection wells, known as class II wells, and any future wells located within the exterior boundaries of the formal Navajo Reservation, and on Navajo Nation tribal trust lands and trust allotments in the Eastern Agency—an area of Navajo Indian land located outside the boundaries of the formal reservation.

The EPA determined that the Navajo Nation’s class II UIC program is at least as stringent as the federal program. The Navajo Nation, which assisted the EPA in implementing and enforcing federal regulations on Navajo lands, modeled its program after the EPA’s program.

The Navajo Nation has worked diligently over the past several years to develop an effective program by enacting the Navajo Nation Safe Drinking Water Act—putting into law UIC regulations, and developing the technical, permitting and enforcement capacity to fully implement the injection well program.

The oil and gas production industry accounts for a large proportion of the fluids injected into the subsurface. When oil and gas are extracted, large amounts of oily salt water, or brine, are also brought to the surface. Contaminated salt water can be very damaging when discharged into surface water, thus it is typically injected into similar formations from which it was extracted.

The federal UIC program is responsible for the permitting, construction, operation and safe closure of injection wells that place fluids underground for storage, enhanced oil/gas recovery or disposal. The program ensures safe operations of injection wells to prevent contamination of underground sources of drinking water.